It’s just design by committee and long-standing efforts for backwards compatibility. Also the people writing the standards are far too familiar with them and thus a bit lost when it comes to making practical decisions.

Whenever you make changes there will be compromises and someone will have reason to be unhappy.

There is no way that eliminating 2.0, in such a way that everything that used to rate as 2.0 now qualifies as conforming to some subset of 2.1, can be justified as backwards compatibility.

Cable manufacturers probably realized that the secret to profits lay in resisting commoditization, beat a path to the table, and made it happen.

I don't think its particularly odd that the specifications are supersets of old versions; indeed that feels pretty common in the standards world. IETF specs are maybe the odd ones out where you typically have to read like ten different RFCs to get good picture of some standard.

Free market of fraud is going on, there should be a cost to lying